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1.
N Engl J Med ; 379(5): 454-463, 2018 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-30067928

RESUMO

BACKGROUND: The treatment of latent infection with Mycobacterium tuberculosis is important in children because of their vulnerability to life-threatening forms of tuberculosis disease. The current standard treatment - 9 months of isoniazid - has been associated with poor adherence and toxic effects, which have hampered the effectiveness of the drug. In adults, treatment with 4 months of rifampin has been shown to be safer and to have higher completion rates than 9 months of isoniazid. METHODS: In this multicenter, open-label trial, we randomly assigned 844 children (<18 years of age) with latent M. tuberculosis infection to receive either 4 months of rifampin or 9 months of isoniazid. The primary outcome was adverse events of grade 1 to 5 that resulted in the permanent discontinuation of a trial drug. Secondary outcomes were treatment adherence, side-effect profile, and efficacy. Independent review panels whose members were unaware of trial-group assignments adjudicated all adverse events and progression to active tuberculosis. RESULTS: Of the children who underwent randomization, 829 were eligible for inclusion in the modified intention-to-treat analysis. A total of 360 of 422 children (85.3%) in the rifampin group completed per-protocol therapy, as compared with 311 of 407 (76.4%) in the isoniazid group (adjusted difference in the rates of treatment completion, 13.4 percentage points; 95% confidence interval [CI], 7.5 to 19.3). There were no significant between-group differences in the rates of adverse events, with fewer than 5% of the children in the combined groups with grade 1 or 2 adverse events that were deemed to be possibly related to a trial drug. Active tuberculosis, including 1 case with resistance to isoniazid, was diagnosed in 2 children in the isoniazid group during 542 person-years of follow-up, as compared with no cases in the rifampin group during 562 person-years (rate difference, -0.37 cases per 100 person-years; 95% CI, -0.88 to 0.14). CONCLUSIONS: Among children under the age of 18 years, treatment with 4 months of rifampin had similar rates of safety and efficacy but a better rate of adherence than 9 months of treatment with isoniazid. (Funded by the Canadian Institutes of Health Research and Conselho Nacional de Pesquisa; ClinicalTrials.gov number, NCT00170209 .).


Assuntos
Antibióticos Antituberculose/administração & dosagem , Antibióticos Antituberculose/efeitos adversos , Isoniazida/administração & dosagem , Isoniazida/efeitos adversos , Tuberculose Latente/tratamento farmacológico , Rifampina/administração & dosagem , Rifampina/efeitos adversos , Adolescente , Criança , Pré-Escolar , Esquema de Medicação , Feminino , Seguimentos , Humanos , Lactente , Análise de Intenção de Tratamento , Masculino , Adesão à Medicação , Segurança do Paciente , Resultado do Tratamento
2.
N Engl J Med ; 379(5): 440-453, 2018 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-30067931

RESUMO

BACKGROUND: A 9-month regimen of isoniazid can prevent active tuberculosis in persons with latent tuberculosis infection. However, the regimen has been associated with poor adherence rates and with toxic effects. METHODS: In an open-label trial conducted in nine countries, we randomly assigned adults with latent tuberculosis infection to receive treatment with a 4-month regimen of rifampin or a 9-month regimen of isoniazid for the prevention of confirmed active tuberculosis within 28 months after randomization. Noninferiority and potential superiority were assessed. Secondary outcomes included clinically diagnosed active tuberculosis, adverse events of grades 3 to 5, and completion of the treatment regimen. Outcomes were adjudicated by independent review panels. RESULTS: Among the 3443 patients in the rifampin group, confirmed active tuberculosis developed in 4 and clinically diagnosed active tuberculosis developed in 4 during 7732 person-years of follow-up, as compared with 4 and 5 patients, respectively, among 3416 patients in the isoniazid group during 7652 person-years of follow-up. The rate differences (rifampin minus isoniazid) were less than 0.01 cases per 100 person-years (95% confidence interval [CI], -0.14 to 0.16) for confirmed active tuberculosis and less than 0.01 cases per 100 person-years (95% CI, -0.23 to 0.22) for confirmed or clinically diagnosed tuberculosis. The upper boundaries of the 95% confidence interval for the rate differences of the confirmed cases and for the confirmed or clinically diagnosed cases of tuberculosis were less than the prespecified noninferiority margin of 0.75 percentage points in cumulative incidence; the rifampin regimen was not superior to the isoniazid regimen. The difference in the treatment-completion rates was 15.1 percentage points (95% CI, 12.7 to 17.4). The rate differences for adverse events of grade 3 to 5 occurring within 146 days (120% of the 4-month planned duration of the rifampin regimen) were -1.1 percentage points (95% CI, -1.9 to -0.4) for all events and -1.2 percentage points (95% CI, -1.7 to -0.7) for hepatotoxic events. CONCLUSIONS: The 4-month regimen of rifampin was not inferior to the 9-month regimen of isoniazid for the prevention of active tuberculosis and was associated with a higher rate of treatment completion and better safety. (Funded by the Canadian Institutes of Health Research and the Australian National Health and Medical Research Council; ClinicalTrials.gov number, NCT00931736 .).


Assuntos
Antibióticos Antituberculose/administração & dosagem , Isoniazida/administração & dosagem , Tuberculose Latente/tratamento farmacológico , Rifampina/administração & dosagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibióticos Antituberculose/efeitos adversos , Esquema de Medicação , Feminino , Seguimentos , Humanos , Isoniazida/efeitos adversos , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Rifampina/efeitos adversos
3.
Microvasc Res ; 135: 104136, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33450295

RESUMO

Reversine, or 2-(4-morpholinoanilino)-6cyclohexylaminopurine, is a 2,6-disubstituted purine derivative. This small molecule exhibits tumor-suppressive activities through different molecular mechanisms. In this study, in vitro and in vivo angiogenic models were used to elucidate the effect of Reversine on angiogenesis in the tumor suppression. Firstly, we grafted osteosarcoma-derived MNNG/HOS cell aggregates onto chick embryonic chorioallantoic membrane (CAM) to examine the vascularization of these grafts following Reversine treatment. Following culture, it was determined that Reversine inhibited MNNG/HOS grafts growth, and decreased the density of blood vessels in the chick CAM. We then used CAM and chick embryonic yolk-sac membrane (YSM) to investigate the effects of Reversine on angiogenesis. The results revealed Reversine inhibited the proliferation of endothelial cells, where cells were mainly arrested at G1/S phase of the cell cycle. Scratch-wound assay with HUVECs revealed that Reversine suppressed cell migration in vitro. Furthermore, endothelial cells tube formation assay and chick aortic arch sprouting assay demonstrated Reversine inhibited the sprouting, migration of endothelial cells. Lastly, qPCR and western blot analyses showed BMP-associated Smad1/5/8 signaling expressions were up-regulated by Reversine treatment. Our results showed that Reversine could suppress tumor growth by inhibiting angiogenesis through BMP signaling, and suggests a potential use of Reversine as an anti-tumor therapy.


Assuntos
Inibidores da Angiogênese/farmacologia , Proteínas Morfogenéticas Ósseas/metabolismo , Neoplasias Ósseas/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Morfolinas/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Osteossarcoma/tratamento farmacológico , Purinas/farmacologia , Proteínas Smad/metabolismo , Animais , Proteínas Morfogenéticas Ósseas/genética , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Embrião de Galinha , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Transdução de Sinais , Proteínas Smad/genética , Proteína Smad1/metabolismo , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo
4.
Exp Cell Res ; 387(1): 111738, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31759057

RESUMO

Nonalcoholic steatohepatitis (NASH) is a major threat to health worldwide. Lipotoxicity and macrophage-mediated inflammation play key roles in the pathogenesis of NASH. In this study, we found that individuals with higher serum LDL-C levels have a higher prevalence of nonalcoholic fatty liver disease (NAFLD) and elevated levels of glutamic-pyruvic transaminase, glutamic-oxalacetic transaminase and alkaline phosphatase. A logistic regression analysis revealed that serum LDL-C level is an independent risk factor for the prevalence and prognosis of NAFLD. In vitro, we used ox-LDL and MßCD-cholesterol to treat Huh7 cells and found that cholesterol loading reduced lysosomal quantity and impaired lysosomal acidification, reducing the number of multivesicular bodies (MVBs) colocalizing with lysosomes. The bafilomycin A1 inhibition of lysosomal function also inhibited lysosomal MVBs degradation, promoting the release of exosomes from the Huh7 cells. Next, we found that cholesterol loading promoted exosome release from the Huh7 cells. The exosomes from the cholesterol-loaded cells increased the ratio of the THP-1 cells positive for the M1 marker (iNOS-1) without affecting the ratio of the cells positive for the M2 marker (CD206). Moreover, an elevated level of miR-122-5p was observed in exosomes derived from the Huh7 cells loaded with cholesterol. While the miR-122-5p mimics promoted THP-1 M1 polarization, downregulating miR-122-5p in the Huh7 cells inhibited the exosome-induced activation of macrophages and macrophage-related inflammation. These findings suggest that cholesterol plays an important role in the development and progression of NASH. Cholesterol-induced lysosomal dysfunction increases exosome release from hepatocytes, resulting in M1 polarization and macrophage-induced inflammation in a miR-122-5p-dependent manner.


Assuntos
Colesterol/metabolismo , Hepatócitos/metabolismo , Lisossomos/metabolismo , Macrófagos/metabolismo , MicroRNAs/metabolismo , Linhagem Celular , Exossomos/metabolismo , Humanos , Inflamação/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Estudos Retrospectivos , Células THP-1
5.
Phys Chem Chem Phys ; 22(5): 2858-2869, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-31950963

RESUMO

The singlet-triplet energy splittings (STES) of dication carbon chains capped by three 16-electron and two 14-electron configuration transition metal termini have been investigated using density functional theory. All five transition metal-capped carbon chains (MCC) exhibit an odd-even STES alternation, suggesting that it is a general feature of the MCCs. Analysis of the frontier molecular orbitals indicates that the frontier and neighboring molecular orbitals (MOs) are π orbitals delocalized over the entire carbon chain, the transition metal termini, and the ancillary ligands. In even and odd metal-carbon chains the HOMOs and LUMOs are nearly degenerate and non-degenerate, respectively, resulting in the even-odd STES alternation. Further analysis of the MOs in the MCCs and the uncapped carbon chains indicate that the STES of the MCCs are determined substantially by the uncapped carbon chain. Other ancillary ligands also play important roles in tuning the energy splitting through their π donor and acceptor abilities. These observations are helpful for the design of cumulene materials exhibiting tunable electronic and optical properties.

6.
Int J Mol Sci ; 21(7)2020 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-32260461

RESUMO

Growing evidence suggests an adverse impact of gut microbiota dysbiosis on human health. However, it remains unclear whether embryonic osteogenesis is affected by maternal gut dysbacteriosis. In this study, we observed that elevated lipopolysaccharide (LPS) levels led to skeletal developmental retardation in an established mouse model of gut microbiota dysbiosis. Using chick embryos exposed to dysbacteriosis-derived LPS, we found restriction in the development of long bones as demonstrated by Alcian blue and alizarin red staining. Micro-CT and histological analysis exhibited decreased trabecular volume, bone mineral density, and collagen production, as well as suppressed osteoblastic gene expression (Ocn, Runx2, Osx, and Dlx5) in chick embryonic phalanges following LPS treatment. Atomic force microscopy manifested decreased roughness of MC3T3-E1 cells and poorly developed matrix vesicles (MVs) in presence of LPS. The expression of the aforementioned osteoblastic genes was suppressed in MC3T3-E1 cells as well. High-throughput RNA sequencing indicated that retinoic acid (RA) may play an important role in LPS-induced osteopenia. The addition of RA suppressed Dlx5 expression in MC3T3-E1 cells, as was also seen when exposed to LPS. Quantitative PCR, Western blot, and immunofluorescent staining showed that retinoic acid receptor α (RARα) was upregulated by LPS or RA treatment, while the expression of DLX5 was downregulated. CYP1B1 expression was increased by LPS treatment in MC3T3-E1 cells, which might be attributed to the increased inflammatory factors and subsequently activated NF-κB signaling. Eventually, blocking RA signals with AGN193109 successfully restored LPS-inhibited osteoblastic gene expression. Taken together, our data reveals that maternal gut microbiota dysbiosis can interfere with bone ossification, in which Dlx5 expression regulated by RA signaling plays an important role.


Assuntos
Doenças Ósseas Metabólicas/genética , Disbiose/genética , Proteínas de Homeodomínio/genética , Lipopolissacarídeos/efeitos adversos , Tretinoína/metabolismo , Animais , Doenças Ósseas Metabólicas/induzido quimicamente , Doenças Ósseas Metabólicas/metabolismo , Linhagem Celular , Embrião de Galinha , Modelos Animais de Doenças , Disbiose/induzido quimicamente , Disbiose/metabolismo , Ectoderma/metabolismo , Feminino , Proteínas de Homeodomínio/metabolismo , Camundongos , Análise de Sequência de RNA
7.
J Cell Physiol ; 234(3): 2593-2605, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30264889

RESUMO

Accumulating data show that the cytotoxicity of bacterial lipopolysaccharides (LPS) from microbiota or infection is associated with many disorders observed in the clinics. However, it is still obscure whether or not embryonic osteogenesis is affected by the LPS exposure during gestation. Using the early chicken embryo model, we could demonstrate that LPS exposure inhibits chondrogenesis of the 8-day chicken embryos by Alcian Blue-staining and osteogenesis of 17-day by Alcian Blue and Alizarin Red staining. Further analysis of the growth plates showed that the length of the proliferating zone (PZ) increases whereas that of the hypertrophic zone (HZ) decreased following LPS exposure. However there is no significant change on cell proliferation in the growth plates. Immunofluorescent staining, western blot analysis, and quantitive polymerase chain reaction revealed that Sox9 and Col2a1 are highly expressed at the messenger RNA level and their protein products are also abundant. LPS exposure causes a downregulation of Runx2 and Col10a1 expression in 8-day hindlimbs, and a suppression of Runx2, Col10a1, and Vegfa expression in 17-day phalanges. Knocking down Sox9 in ATDC5 cells by small interfering RNA transfection lead to the expression reduction of Col2a1, Runx2, and Col10a1, implying the vital role of Sox9 in the process of LPS-induced delay in the transition from proliferating chondrocytes to hypertrophic chondrocytes in the growth plate. In the presence of LPS, the antioxidant defense regulator nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is highly expressed, and the activities of superoxide dismutase 1 (SOD1), SOD2, and glutaredoxin rise in 17-day phalanges and ADTC5 cells. Simultaneously, an increase of intracellular ROS is observed. When Nrf2 expression was knocked down in ATDC5 cells, the expressions of Sox9, Col2a1, Runx2, Col10a1, and Vegfa were also going down as well. Taken together, our current data suggest that LPS exposure during gestation could restrict the chondrocytes conversion from proliferating to hypertrophic in the growth plate, in which LPS-induced Sox9 plays a crucial role to trigger the cascade of downstream genes by excessive ROS production and Nrf2 elevation.


Assuntos
Condrócitos/efeitos dos fármacos , Condrogênese/efeitos dos fármacos , Lâmina de Crescimento/metabolismo , Lipopolissacarídeos/farmacologia , Fatores de Transcrição SOX9/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Condrócitos/metabolismo , Condrogênese/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Lâmina de Crescimento/efeitos dos fármacos , Humanos , Hipertrofia/tratamento farmacológico , Hipertrofia/metabolismo , Microbiota , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia
8.
J Cell Physiol ; 234(6): 9826-9838, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30362583

RESUMO

In this study, we investigated the effect of caffeine overexposure on corneal innervation in the early chicken embryo. Caffeine administration restricted corneal innervation by affecting trigeminal nerve development. Immunohistochemistry for phospho-Histone3 (pHIS3) and C-caspase3 revealed that cell survival was repressed by caffeine administration. Whole-mount in situ hybridization against semaphorin 3A (Sema3A) and neuropilin-1 (Nrp1) showed that both caffeine and 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AAPH, a free radical generator) administration upregulates the expression of both Sema3A and Nrp1. Next, we demonstrated that lens ablation in the developing chicken embryos significantly affected NF-labeled periocular nerve fascicles and innervation to the central eye region. Subsequently, we used a neuroblastoma cell line to investigate in vitro whether or not Sema3A-Nrp1 signaling exerts a key role on the caffeine-suppressed neuron survival. Knocking-down Sema3A through transfection with Sema3A-siRNA dramatically decreased the responsiveness of cells to caffeine administration, as well as cell apoptosis. We suggest that Sema3A-Nrp1 signaling regulates Trp53 and Cdkn1a through Slit2-Robo1 and Ephb2. Taken together, we speculate here that caffeine-enhanced reactive oxygen species upregulates Sema3A-Nrp1 expression in the lens and periocular tissues, resulting in corneal cell apoptosis, accompanied by its chemorepellent role on the invasion of the developing cornea by trigeminal sensory fibers.


Assuntos
Neuropilina-1/metabolismo , Semaforina-3A/metabolismo , Animais , Cafeína/farmacologia , Linhagem Celular Tumoral , Embrião de Galinha , Córnea , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Técnicas de Silenciamento de Genes , Humanos , Cristalino , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neuroblastoma , Organogênese , Espécies Reativas de Oxigênio , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Proteínas Roundabout
9.
J Cell Physiol ; 234(9): 15167-15181, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30671960

RESUMO

Dexamethasone (Dex), a synthetic glucocorticoid (GC) with long-lasting treatment effects, has been proved to exert a modulatory effect on osteoblast proliferation and differentiation during embryonic osteogenesis. However, it is still controversial if Dex exposure influences endochondral ossification and the underlying mechanism. In this study, chick embryos in vivo and preosteoblast cell cultures in vitro were utilized to investigate the effects of Dex on osteoblast formation and differentiation during the skeletal development. We first demonstrated that Dex exposure could shorten the long bones of 17-day chick embryos in vivo, and also downregulated the expressions of osteogenesis-related genes. Next, we established that Dex exposure inhibited the proliferation and viability of preosteoblasts-MC3TC-E1 cells, and the addition of insulin-like growth factor 1 (IGF-1) could dramatically rescue these negative effects. On the basis of remarkable changes in the rescue experiments, we next verified the important role of angiogenesis in osteogenesis by culturing isolated embryonic phalanges in Dulbecco's modified Eagle's medium culture or on the chick chorioallantoic membrane (CAM). Then, we transplanted MC3T3-E1 cell masses onto the CAM. The data showed that Dex exposure reduced the vessel density within the developed cell mass, concomitantly with the downregulation of IGF-1 pathway. We verified that the inhibition of blood vessel formation caused by Dex could be rescued by IGF-1 treatment using the CAM angiogenesis model. Eventually, we demonstrated that the shortened length of the phalanges in the presence of Dex could be reversed by IGF-1 addition. In summary, these findings suggested that the inhibition of Igf-1 signal caused by Dex exposure exerts a detrimental impact on the formation of osteoblasts and angiogenesis, which consequently shortens long bones during osteogenesis.

10.
Artigo em Inglês | MEDLINE | ID: mdl-29941653

RESUMO

Although the stability of ß-lactam antibiotics is a known issue, none of the previously reported bioanalytical methods had an adequate evaluation of the stability of these drugs. In the current study, the stability of cefepime, meropenem, piperacillin, and tazobactam under various conditions was comprehensively evaluated. The evaluated parameters included stock solution stability, short-term stability, long-term stability, freeze-thaw stability, processed sample stability, and whole-blood stability. When stored at -20°C, the stock solution of meropenem in methanol was stable for up to 3 weeks, and the stock solutions of cefepime, piperacillin, and tazobactam were stable for up to 6 weeks. All four antibiotics were stable in human plasma for up to 3 months when stored at -80°C and were stable in whole blood for up to 4 h at room temperature. Short-term stability results indicated that all four ß-lactams were stable at room temperature for 2 h, but substantial degradation was observed when the plasma samples were stored at room temperature for 24 h, with the degradation rates for cefepime, meropenem, piperacillin, and tazobactam being 30.1%, 75.6%, 49.0%, and 37.7%, respectively. Because the stability information is method independent, our stability results can be used as a reference by other research groups that work with these antibiotics.


Assuntos
Antibacterianos/metabolismo , Cefepima/metabolismo , Meropeném/metabolismo , Piperacilina/metabolismo , Tazobactam/metabolismo , Cromatografia Líquida , Estabilidade de Medicamentos , Humanos , Espectrometria de Massas em Tandem , Temperatura
11.
Artigo em Inglês | MEDLINE | ID: mdl-29941654

RESUMO

The highly variable pharmacokinetics of ß-lactam antibiotics and ß-lactamase inhibitors poses a significant challenge to clinicians in ensuring appropriate antibiotic doses in critically ill patients. Therefore, routine monitoring of plasma concentrations is important for individualization of antimicrobial therapy. Accordingly, a simple and robust analytical method for the simultaneous measurement of multiple ß-lactam antibiotics and ß-lactamase inhibitors is highly desirable to ensure quick decisions on dose adjustments. In this study, a sensitive, simple, and robust method for the simultaneous quantification of cefepime, meropenem, piperacillin, and tazobactam in human plasma was developed and rigorously validated according to FDA guidance. Sample extraction was accomplished by simple protein precipitation. Chromatographic separation of analytes was achieved using stepwise gradient elution. Analytes were monitored using tandem mass spectrometry (MS/MS) with a turbo ion spray source in positive multiple-reaction-monitoring mode. The calibration curve ranged from 0.5 to 150 µg/ml for cefepime, 0.1 to 150 µg/ml for meropenem and piperacillin, and 0.25 to 150 µg/ml for tazobactam. Inter- and intraday precision and accuracy, sensitivity, selectivity, dilution integrity, matrix effect, extraction recovery, and hemolysis effect were investigated for all four analytes, and the results met the acceptance criteria. Compared to other reported methods, our method is more robust because of the combination of the following features: (i) a simple sample extraction procedure, (ii) a short sample run time, (iii) a wide dynamic range, and (iv) the small plasma sample volume needed. Since our method already covers ß-lactams and a ß-lactamase inhibitor with highly heterogeneous physicochemical properties, further antibiotic candidates may easily be incorporated into this multianalyte method.


Assuntos
Antibacterianos/sangue , Cefepima/sangue , Cromatografia Líquida/métodos , Meropeném/sangue , Piperacilina/sangue , Espectrometria de Massas em Tandem/métodos , Tazobactam/sangue , beta-Lactamas/farmacocinética , Humanos , Sensibilidade e Especificidade
12.
Cell Physiol Biochem ; 48(5): 2084-2090, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30099448

RESUMO

BACKGROUND/AIMS: Angiogenesis plays a key role during embryonic development. The vascular endothelin (ET) system is involved in the regulation of angiogenesis. Lipopolysaccharides (LPS) could induce angiogenesis. The effects of ET blockers on baseline and LPS-stimulated angiogenesis during embryonic development remain unknown so far. METHODS: The blood vessel density (BVD) of chorioallantoic membranes (CAMs), which were treated with saline (control), LPS, and/or BQ123 and the ETB blocker BQ788, were quantified and analyzed using an IPP 6.0 image analysis program. Moreover, the expressions of ET-1, ET-2, ET3, ET receptor A (ETRA), ET receptor B (ETRB) and VEGFR2 mRNA during embryogenesis were analyzed by semi-quantitative RT-PCR. RESULTS: All components of the ET system are detectable during chicken embryogenesis. LPS increased angiogenesis substantially. This process was completely blocked by the treatment of a combination of the ETA receptor blockers-BQ123 and the ETB receptor blocker BQ788. This effect was accompanied by a decrease in ETRA, ETRB, and VEGFR2 gene expression. However, the baseline angiogenesis was not affected by combined ETA/ETB receptor blockade. CONCLUSION: During chicken embryogenesis, the LPS-stimulated angiogenesis, but not baseline angiogenesis, is sensitive to combined ETA/ETB receptor blockade.


Assuntos
Antagonistas do Receptor de Endotelina B/farmacologia , Lipopolissacarídeos/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Receptor de Endotelina A/metabolismo , Receptor de Endotelina B/metabolismo , Animais , Galinhas , Membrana Corioalantoide/efeitos dos fármacos , Membrana Corioalantoide/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Endotelina-1/genética , Endotelina-1/metabolismo , Oligopeptídeos/farmacologia , Peptídeos Cíclicos/farmacologia , Piperidinas/farmacologia , Receptor de Endotelina A/química , Receptor de Endotelina A/genética , Receptor de Endotelina B/química , Receptor de Endotelina B/genética , Transdução de Sinais/efeitos dos fármacos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
13.
Cell Immunol ; 332: 111-120, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30103942

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease in many developed and developing countries worldwide. It has been well established that the chronic sterile inflammation caused by the NLRP3 inflammasome is closely related to NAFLD development. Kupffer cells (KCs) are involved in the pathogenesis of various liver diseases. We used methionine choline-deficient diets to establish a mouse nonalcoholic steatohepatitis (NASH) model. The expression and formation of the NLRP3 inflammasome in the KCs from the mouse and cell models were determined by Western blotting and co-immunoprecipitation. Evidence of mitochondrial DNA (mtDNA) release was determined by live cell labeling and imaging. KCs and the NLRP3 inflammasome exerted proinflammatory effects on the development and progression of NASH through secretion of the proinflammatory cytokine IL-1ß. NLRP3, ASC and Caspase-1 protein expression levels in KCs from NASH mouse livers were significantly higher than those in KCs from NLRP3-/- mice, and the number of NLRP3 inflammasome protein complexes was significantly higher in KCs from NASH mouse livers, whereas these protein complexes could not be formed in NLRP3-/- mice. In in vitro experiments, palmitic acid (PA) decreased the mitochondrial membrane potential and subsequently induced mtDNA release from the mitochondria to the cytoplasm. NLRP3 inflammasome expression was substantially increased, and mtDNA-NLRP3 inflammasome complexes formed upon PA stimulation. Our data suggest that mtDNA released from mitochondria during PA stimulation causes NLRP3 inflammasome activation, providing a missing link between NLRP3 inflammasome activation and NASH development, via binding of cytosolic mtDNA to the NLRP3 inflammasome.


Assuntos
DNA Mitocondrial/metabolismo , Ácidos Graxos/metabolismo , Inflamassomos/metabolismo , Células de Kupffer/metabolismo , Mitocôndrias/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Animais , Caspase 1/metabolismo , Citoplasma/metabolismo , Modelos Animais de Doenças , Inflamação/metabolismo , Interleucina-1beta/metabolismo , Masculino , Potencial da Membrana Mitocondrial/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/metabolismo
14.
J Environ Manage ; 196: 443-457, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28342339

RESUMO

The analysis and prediction of air pollutants are of great significance in environmental research today since airborne pollution is a substantial threat, especially in urban agglomerations of China. To develop more effective warning systems and management advice, the authorities and city dwellers need more accurate forecasts of the air pollution. Most previous analysis systems were based on costly observation apparatus at fixed sites, forecasting models were usually built on observations within a certain range, and some observations contained biases. In this paper, a novel and effective framework, termed HML-AFNN, was successfully developed to analyse and forecast the concentration of particular matter (PM2.5) for a selected number of forward time steps. In a simulation of the trajectory of air pollutants, the high-dimension association rules (HDAR) approach considered the tempo-spatial relations, as well as the meteorological and geographical factors of the ambient regions, as parameters. In addition, the learning vector quantization (LVQ) network was adopted to select the appropriate inputs to improve the efficiency of the training process. Moreover, an adaptive fuzzy neural network (AFNN), a combination of neural and fuzzy logic, was utilized to analyse and predict the PM2.5 concentration. The experiment results of our study on two major urban agglomerations of China, the Jing-Jin-Ji area and Pearl River Delta, over a period of more than one year demonstrated that the developed hybrid HML-AFNN model outperforms a plain AFNN, an HM-AFNN model without LVQ and the least squares support vector machines (LS-SVM); this superior performance can be determined from the values of several error indexes, including MAE, MAPE and band errors. This hybrid model, which has robust and accurate results, shows the potential to be a political and administrative method to issue effective early warnings and to design suitable abatement strategies.


Assuntos
Poluição do Ar , Monitoramento Ambiental , Poluentes Atmosféricos , China , Material Particulado
15.
J Infect Dis ; 214(6): 906-15, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27377744

RESUMO

Pellino 1 positively regulates Toll-like receptor 4 signaling by regulating tumor necrosis factor receptor-associated factor 3 (TRAF3) degradation and is suppressed with the induction of endotoxin tolerance. However, the role of TRAF3 in endotoxin tolerance is largely unknown. In this study, we found that lipopolysaccharide (LPS) stimulation decreased TARF3 protein expression in mouse Kupffer cells (KCs) and liver tissues, whereas endotoxin tolerization abrogated this effect. Degradative TRAF3 K48-linked ubiquitination and the cytoplasmic translocation of the MYD88-associated multiprotein complex were significantly inhibited in tolerized KCs, which led to markedly impaired activation of MYD88-dependent JNK and p38 and downregulation of inflammatory cytokines. TRAF3 ablation failed to induce a fully endotoxin-tolerant state in RAW264.7 cells. Pellino 1 knockdown in Raw264.7 cells did not impair induction of cIAP2 in response to LPS but inhibited the K63-linked ubiquitination of cellular inhibitor of apoptosis protein 2 (cIAP2) and K48-linked ubiquitination of TRAF3 protein. We also found upregulation of Pellino 1 and downregulation of TRAF3 in liver tissues of patients with cholangitis. Our findings reveal a novel mechanism that endotoxin tolerance reprograms mitogen-activated protein kinase signaling by suppressing Pellino 1-mediated K63-linked ubiquitination of cIAP2, K48-linked ubiquitination, and degradation of TRAF3.


Assuntos
Endotoxinas/toxicidade , Proteínas Inibidoras de Apoptose/metabolismo , Proteínas Nucleares/metabolismo , Fator 3 Associado a Receptor de TNF/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Animais , Proteína 3 com Repetições IAP de Baculovírus , Células Cultivadas , Células de Kupffer/fisiologia , Fígado/patologia , Macrófagos , Masculino , Camundongos Endogâmicos C57BL , Proteólise
16.
J Surg Res ; 193(2): 781-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25145904

RESUMO

BACKGROUND: Traditional splenic preservation surgery involves considerable difficulties, high risks, and numerous postoperative complications. In this study, we applied radiofrequency ablation (RFA) to splenic preservation and explored its clinical value. METHODS: The clinical data of 129 patients with traumatic splenic rupture who received surgery in our hospital from September 2008-June 2013 were retrospectively analyzed. According to the operation methods, these patients were divided into three groups: 35 patients received splenic preservation surgery with RFA-assisted technique (RFA + suture repair group), 78 patients received splenic preservation surgery without RFA (traditional operation group), and 46 patients received splenectomy (splenectomy group). Preoperative, intraoperative, and postoperative-related parameters of the former two groups were compared. The postoperative complications and immunologic parameters of patients with preserved spleens were compared with those of patients who underwent splenectomy. RESULT: In the RFA + suture repair group, 34 cases successfully underwent splenic preservation surgery. Meanwhile, 49 cases successfully underwent spleen preservation surgery in the traditional operation group. RFA + suture repair group had shorter mean operation time (79 ± 22 versus 119 ± 26 min, P < 0.05), less bleeding during surgery (115 ± 67 versus 235 ± 155 mL, P < 0.05), and less intraoperative transfusion (14% versus 36%, P < 0.05). The postoperative bleeding and hospital-stay duration were remarkably lower than those in the traditional operation group (100 ± 52 versus 219 ± 93 mL and 7.1 ± 1.4 d versus 11.7 ± 2.8 d, respectively, P < 0.05). The spleen-preserving patients showed better results than the splenectomy group did for some parameters related to complications and immunology. CONCLUSIONS: Compared with traditional splenic preservation, RFA is simple and feasible, and it can greatly benefit the spleen preservation operation.


Assuntos
Técnicas de Ablação/estatística & dados numéricos , Ruptura Esplênica/cirurgia , Técnicas de Ablação/métodos , Adulto , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Esplenectomia , Adulto Jovem
17.
Nat Commun ; 15(1): 1462, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38368405

RESUMO

Ethylene/α-olefin copolymers are produced in huge scale and widely used, but their after-use disposal has caused plastic pollution problems. Their chemical inertness made chemical re/upcycling difficult. Ideally, PE materials should be made de novo to have a circular closed-loop lifecycle. However, synthesis of circular ethylene/α-olefin copolymers, including high-volume, linear low-density PE as well as high-value olefin elastomers and block copolymers, presents a particular challenge due to difficulties in introducing branches while simultaneously installing chemical recyclability and directly using industrial ethylene and α-olefin feedstocks. Here we show that coupling of industrial coordination copolymerization of ethylene and α-olefins with a designed functionalized chain-transfer agent, followed by modular assembly of the resulting AB telechelic polyolefin building blocks by polycondensation, affords a series of ester-linked PE-based copolymers. These new materials not only retain thermomechanical properties of PE-based materials but also exhibit full chemical circularity via simple transesterification and markedly enhanced adhesion to polar surfaces.

18.
Adv Biol (Weinh) ; 8(5): e2300673, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38456367

RESUMO

This research utilized single-cell RNA sequencing to map the immune cell landscape in sepsis, revealing 28 distinct cell clusters and categorizing them into nine major types. Delving into the monocyte/macrophage subclusters, 12 unique subclusters are identified and pathway enrichment analyses are conducted using KEGG and GO, discovering enriched pathways such as oxidative phosphorylation and antigen processing. Further GSVA and AUCell assessments show varied activation of interferon pathways, especially in subclusters 4 and 11. The clinical correlation analysis reveals genes significantly linked to survival outcomes. Additionally, cellular differentiation in these subclusters is explored. Building on these insights, the differential gene expression within these subclusters is specifically scrutinized, which reveal MYOF as a key gene with elevated expression levels in the survivor group. This finding is further supported by in-depth pathway enrichment analysis and the examination of cellular differentiation trajectories, where MYOF's role became evident in the context of immune response regulation and sepsis progression. Validating the role of the MYOF gene in sepsis, a dose-dependent response to LPS in THP-1 cells and C57 mice is observed. Finally, inter-cellular communications are analyzed, particularly focusing on the MYOF+Mono/Macro subcluster, which indicates a pivotal role in immune regulation and potential therapeutic targeting.


Assuntos
Macrófagos , Monócitos , Sepse , Análise de Célula Única , Humanos , Sepse/imunologia , Sepse/genética , Sepse/metabolismo , Monócitos/imunologia , Monócitos/metabolismo , Camundongos , Análise de Célula Única/métodos , Macrófagos/imunologia , Macrófagos/metabolismo , Animais , Prognóstico , Camundongos Endogâmicos C57BL , Masculino , Células THP-1 , Feminino
19.
J Surg Res ; 184(2): 1035-44, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23721934

RESUMO

BACKGROUND/AIMS: Endotoxin (lipopolysaccharide, LPS)-induced acute liver injury was attenuated by endotoxin tolerance (ET), which is characterized by phosphatidylinositol 3-kinase pathway/Akt signaling. Glycogen synthase kinase 3 (GSK-3) acts downstream of phosphatidylinositol 3-kinase pathway/Akt and GSK-3 inhibitor protects against organic injury. This study evaluates the hypothesis that ET attenuated LPS-induced liver injury through inhibiting GSK-3 functional activity and downstream signaling. METHODS: Sprague-Dawley rats with or without low-dose LPS pretreatment were challenged with or without large dose of LPS and subsequently received studies. Serum tumor necrosis factor-alpha, interleukin-10, alanine aminotransferase, lactate dehydrogenase, and total bilirubin levels were analyzed, morphology of liver tissue was performed, glycogen content, myeloperoxidase content, phagocytosis activity of Kupffer cells, and the expression and inhibitory phosphorylation as well as kinase activity of GSK-3 were examined. Survival after LPS administration was also determined. RESULTS: LPS induced significant increases of serum TNF-α, alanine aminotransferase, lactate dehydrogenase, and total bilirubin (P < 0.05), which were companied by obvious alterations in liver: the injury of liver tissue, the decrease of glycogen, the infiltration of neutrophils, and the enhancement of phagocytosis of Kupffer cells (P < 0.05). LPS pretreatment significantly attenuated these alterations, promoted the inhibitory phosphorylation of GSK-3 and inhibited its kinase activity, and improved the survival rate (P < 0.05). CONCLUSIONS: ET attenuated LPS-induced acute liver injury through inhibiting GSK-3 functional activity and its downstream signaling.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Endotoxinas/efeitos adversos , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Lipopolissacarídeos/efeitos adversos , Transdução de Sinais/efeitos dos fármacos , Alanina Transaminase/metabolismo , Animais , Bilirrubina/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Quinase 3 da Glicogênio Sintase/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/metabolismo , Interleucina-10/metabolismo , L-Lactato Desidrogenase/metabolismo , Masculino , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo
20.
Dig Dis Sci ; 58(3): 835-40, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23007732

RESUMO

BACKGROUND: Surgical resection remains the optimal therapy for cirrhotic patients with hepatocellular carcinoma (HCC) that are not suitable for liver transplantation (LT). Recently, various innovative techniques for liver resection have been developed. AIM: The aim of the study was to compare radiofrequency-assisted parenchyma transection (RF-PT) with the traditional clamp-crushing (CC) technique to explore the preferred therapy in cirrhotic patients with HCC. METHODS: From January 2009 to December 2010, 75 cirrhotic patients with HCC who underwent hepatectomy were randomized to RF-PT (group 1, n = 38) or CC-PT (group 2, n = 37) groups. The primary endpoint was intraoperative blood loss. The secondary endpoints included hepatic transection time, total operating time, postoperative morbidity, mortality, length of intensive care unit and hospital stays, and liver function. RESULTS: The characteristics of the two patient groups were closely matched. The Pringle maneuver was not used in RF-PT patients. The blood loss of the RF-PT group, total or during transection, was significantly lower than that of the CC-PT group (385 vs. 545 ml, p = 0.001; 105 vs. 260 ml, p = 0.000, respectively). Compared with CC-PT patients, the morbidity of the RF-PT group was lower though not statistically significant (28.9 vs. 38.8 %, p = 0.197). One death occurred in the RF-PT group 12 days postoperative due to a large area cerebral embolism. CONCLUSION: RF-PT is a safe and feasible surgical resection method for patients with cirrhosis and concomitant HCC. In addition, RF-PT results in lower blood loss and lower morbidity than the CC technique during liver resection.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hepatectomia/métodos , Cirrose Hepática/cirurgia , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Ablação por Cateter , Feminino , Humanos , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
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